The present invention relates to a reel for use with a slot machine, and more particularly, it relates to a reel structure suitable for a slot machine whose reel is driven by an electric motor.
In general, a slot machine is provided with a plurality of reels each of which has symbols disposed on its outer periphery. On starting a game, these reels are simultaneously rotated, and when the reels are stopped, whether there is a win or not is detected in accordance with a combination of symbols positioned on a winning line.
In conventional slot machines, the reels have been driven by a force generated by a pulling action of a start lever. However, more recently, these reels have been driven by an electric motor. Among these latter types of slot machines, if a stepping motor is used, the detection of the stopped position of the rotating reels, that is, the discrimination of symbols stopped on the winning line, is determined by the number of drive pulses supplied to the stepping motor. This arrangement is very convenient because the detection of a win is carried out with ease.
Stepping motors have in general a low torque, so that if the reels for a slot machine are driven by such a stepping motor, a difficulty arises because of its response characteristics, particularly at the time of starting the machine. In other words, conventional reels are not sufficiently light in weight, and have a large inertial mass. Therefore, it takes a fairly long time for a reel to reach a constant speed of rotation.
In order to solve this problem, it is possible to make the reel thinner, or to use a skeleton frame structure for the reel. However, when lighter weight of the reel is achieved in this way, it tends to jeopardize the strength thereof. Slot machines are often used quite repetitively, so that the rotation and stopping of the reel occur quite frequently. As a result, if the strength particularly at the connection between the reel and a drive shaft of the electric motor becomes insufficient due to the pursuit of lighter weight, undesirable play occurs at this connection or an eccentric rotation of the reel results, and so the durability of the reel decreases.